I had exactly the same problem a few months back with the false neutral, so i took the bike in to the shop, and was told that i had a 'slightly' worn 'selector drum detent wheel'.
Ordered that and a new 'main selector spring', but then 2 days later Fowler's added a week on to the delivery of the detent wheel, so i cancelled it and just had the spring fitted as i needed the bike back quickly, and it fixed the problem.
***NOTE***
I just noticed you posting earlier about not using the clutch when changing gear?
The clutch has been put there for a reason, i would seriously try and get out of that habit! :rolleyes
Ordered that and a new 'main selector spring', but then 2 days later Fowler's added a week on to the delivery of the detent wheel, so i cancelled it and just had the spring fitted as i needed the bike back quickly, and it fixed the problem.

***NOTE***
I just noticed you posting earlier about not using the clutch when changing gear?
The clutch has been put there for a reason, i would seriously try and get out of that habit! :rolleyes
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